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  <font size="+3">&#8592;</font> <a href="https://hosseinmoein.github.io/DataFrame/docs/HTML/DataFrame.html">Back to Documentations</a><BR><BR>
  
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        <th>Signature</th> <th>Description</th> <th>Parameters</th>
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<pre class="code_syntax" style="color:#000000;background:#ffffff00;"><span class="line_wrapper"><span style="color:#800000; font-weight:bold; ">template</span><span style="color:#800080; ">&lt;</span><span style="color:#800000; font-weight:bold; ">typename</span> T<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> I_V<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> <span style="color:#808030; ">.</span><span style="color:#808030; ">.</span><span style="color:#808030; ">.</span> Ts<span style="color:#800080; ">&gt;</span></span>
<span class="line_wrapper">DataFrame</span>
<span class="line_wrapper">groupby1<span style="color:#808030; ">(</span><span style="color:#800000; font-weight:bold; ">const</span> <span style="color:#800000; font-weight:bold; ">char</span> <span style="color:#808030; ">*</span>col_name<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         I_V <span style="color:#808030; ">&amp;</span><span style="color:#808030; ">&amp;</span>idx_visitor<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         Ts<span style="color:#808030; ">&amp;</span><span style="color:#808030; ">&amp;</span> <span style="color:#808030; ">.</span><span style="color:#808030; ">.</span><span style="color:#808030; ">.</span> args<span style="color:#808030; ">)</span> <span style="color:#800000; font-weight:bold; ">const</span><span style="color:#800080; ">;</span></span>
<span class="line_wrapper"></span></pre>
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      <td>
        This method groups the DataFrame by the named column of type T. The group-by'ing is done by equality. The comparison and equality operators must be well defined for type T. It returns a new DataFrame that has been group-by'ed.<BR>
        The summarization of columns is specified by a list of 3-member-tuples (triples) of the following format:<BR>
        <OL>
           <LI>Current DataFrame column name</LI>
           <LI>Column name for the new bucketized DataFrame</LI>
           <LI>A visitor to aggregate current column to new column</LI>
        </OL>

        You must also specify how the index column is summarized, by providing a visitor.<BR>
        If the named column is other than index column, then the returned DataFrame also has a column with the same name which has the unique values of the named column.<BR>
        Also see bucketize().<BR>
      </td>
      <td width="33%">
        <B>T</B>: Type of groupby column. In case if index, it is type of index<BR>
        <B>I_V</B>: Type of visitor to be used to summarize the index column<BR>
        <B>Ts</B>: Types of triples to specify the column summarization<BR>
        <B>col_name</B>: Name of the grouop-by'ing column<BR>
        <B>idx_visitor</B>: A visitor to specify the index summarization<BR>
        <B>args</B>: List of triples to specify the column summarization<BR>
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<pre class="code_syntax" style="color:#000000;background:#ffffff00;"><span class="line_wrapper"><span style="color:#800000; font-weight:bold; ">template</span><span style="color:#800080; ">&lt;</span><span style="color:#800000; font-weight:bold; ">typename</span> T1<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> T2<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> I_V<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         <span style="color:#800000; font-weight:bold; ">typename</span> <span style="color:#808030; ">.</span><span style="color:#808030; ">.</span><span style="color:#808030; ">.</span> Ts<span style="color:#800080; ">&gt;</span></span>
<span class="line_wrapper">DataFrame</span>
<span class="line_wrapper">groupby2<span style="color:#808030; ">(</span><span style="color:#800000; font-weight:bold; ">const</span> <span style="color:#800000; font-weight:bold; ">char</span> <span style="color:#808030; ">*</span>col_name1<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         <span style="color:#800000; font-weight:bold; ">const</span> <span style="color:#800000; font-weight:bold; ">char</span> <span style="color:#808030; ">*</span>col_name2<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         I_V <span style="color:#808030; ">&amp;</span><span style="color:#808030; ">&amp;</span>idx_visitor<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         Ts<span style="color:#808030; ">&amp;</span><span style="color:#808030; ">&amp;</span> <span style="color:#808030; ">.</span><span style="color:#808030; ">.</span><span style="color:#808030; ">.</span> args<span style="color:#808030; ">)</span> <span style="color:#800000; font-weight:bold; ">const</span><span style="color:#800080; ">;</span></span>
<span class="line_wrapper"></span></pre>
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      <td>
        This is the same as above groupby1() but it groups by two columns<BR>
      </td>
      <td>
        <B>T1</B>: Type of first groupby column. In case if index, it is type of index<BR>
        <B>T2</B>: Type of second groupby column. In case if index, it is type of index<BR>
        <B>Ts</B>: Types of triples to specify the column summarization<BR>
        <B>col_name1</B>: Name of the first grouop-by'ing column<BR>
        <B>col_name2</B>: Name of the second grouop-by'ing column<BR>
        <B>idx_visitor</B>: A visitor to specify the index summarization<BR>
        <B>args</B>: List of triples to specify the column summarization<BR>
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<pre class="code_syntax" style="color:#000000;background:#ffffff00;"><span class="line_wrapper"><span style="color:#800000; font-weight:bold; ">template</span><span style="color:#800080; ">&lt;</span><span style="color:#800000; font-weight:bold; ">typename</span> T1<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> T2<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> T3<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         <span style="color:#800000; font-weight:bold; ">typename</span> I_V<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> <span style="color:#808030; ">.</span><span style="color:#808030; ">.</span><span style="color:#808030; ">.</span> Ts<span style="color:#800080; ">&gt;</span></span>
<span class="line_wrapper">DataFrame</span>
<span class="line_wrapper">groupby3<span style="color:#808030; ">(</span><span style="color:#800000; font-weight:bold; ">const</span> <span style="color:#800000; font-weight:bold; ">char</span> <span style="color:#808030; ">*</span>col_name1<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         <span style="color:#800000; font-weight:bold; ">const</span> <span style="color:#800000; font-weight:bold; ">char</span> <span style="color:#808030; ">*</span>col_name2<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         <span style="color:#800000; font-weight:bold; ">const</span> <span style="color:#800000; font-weight:bold; ">char</span> <span style="color:#808030; ">*</span>col_name3<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         I_V <span style="color:#808030; ">&amp;</span><span style="color:#808030; ">&amp;</span>idx_visitor<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         Ts<span style="color:#808030; ">&amp;</span><span style="color:#808030; ">&amp;</span> <span style="color:#808030; ">.</span><span style="color:#808030; ">.</span><span style="color:#808030; ">.</span> args<span style="color:#808030; ">)</span> <span style="color:#800000; font-weight:bold; ">const</span><span style="color:#800080; ">;</span></span>
<span class="line_wrapper"></span></pre>
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      <td>
        This is the same as above groupby2() but it groups by three columns<BR>
      </td>
      <td>
        <B>T1</B>: Type of first groupby column. In case if index, it is type of index<BR>
        <B>T2</B>: Type of second groupby column. In case if index, it is type of index<BR>
        <B>T3</B>: Type of third groupby column. In case if index, it is type of index<BR>
        <B>Ts</B>: Types of triples to specify the column summarization<BR>
        <B>col_name1</B>: Name of the first grouop-by'ing column<BR>
        <B>col_name2</B>: Name of the second grouop-by'ing column<BR>
        <B>col_name3</B>: Name of the third grouop-by'ing column<BR>
        <B>idx_visitor</B>: A visitor to specify the index summarization<BR>
        <B>args</B>: List of triples to specify the column summarization<BR>
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<pre class="code_syntax" style="color:#000000;background:#ffffff00;"><span class="line_wrapper"><span style="color:#800000; font-weight:bold; ">template</span><span style="color:#800080; ">&lt;</span><span style="color:#800000; font-weight:bold; ">typename</span> T<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> I_V<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> <span style="color:#808030; ">.</span><span style="color:#808030; ">.</span><span style="color:#808030; ">.</span> Ts<span style="color:#800080; ">&gt;</span></span>
<span class="line_wrapper"><span style="color:#666616; ">std</span><span style="color:#800080; ">::</span>future<span style="color:#800080; ">&lt;</span>DataFrame<span style="color:#800080; ">&gt;</span></span>
<span class="line_wrapper">groupby1_async<span style="color:#808030; ">(</span><span style="color:#800000; font-weight:bold; ">const</span> <span style="color:#800000; font-weight:bold; ">char</span> <span style="color:#808030; ">*</span>col_name<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">               I_V <span style="color:#808030; ">&amp;</span><span style="color:#808030; ">&amp;</span>idx_visitor<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">               Ts<span style="color:#808030; ">&amp;</span><span style="color:#808030; ">&amp;</span> <span style="color:#808030; ">.</span><span style="color:#808030; ">.</span><span style="color:#808030; ">.</span> args<span style="color:#808030; ">)</span> <span style="color:#800000; font-weight:bold; ">const</span><span style="color:#800080; ">;</span></span>
<span class="line_wrapper"></span></pre>
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      <td>
        Same as groupby1() above, but executed asynchronously
      </td>
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<pre class="code_syntax" style="color:#000000;background:#ffffff00;"><span class="line_wrapper"><span style="color:#800000; font-weight:bold; ">template</span><span style="color:#800080; ">&lt;</span><span style="color:#800000; font-weight:bold; ">typename</span> T1<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> T2<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> I_V<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         <span style="color:#800000; font-weight:bold; ">typename</span> <span style="color:#808030; ">.</span><span style="color:#808030; ">.</span><span style="color:#808030; ">.</span> Ts<span style="color:#800080; ">&gt;</span></span>
<span class="line_wrapper"><span style="color:#666616; ">std</span><span style="color:#800080; ">::</span>future<span style="color:#800080; ">&lt;</span>DataFrame<span style="color:#800080; ">&gt;</span></span>
<span class="line_wrapper">groupby2_async<span style="color:#808030; ">(</span><span style="color:#800000; font-weight:bold; ">const</span> <span style="color:#800000; font-weight:bold; ">char</span> <span style="color:#808030; ">*</span>col_name1<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">               <span style="color:#800000; font-weight:bold; ">const</span> <span style="color:#800000; font-weight:bold; ">char</span> <span style="color:#808030; ">*</span>col_name2<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">               I_V <span style="color:#808030; ">&amp;</span><span style="color:#808030; ">&amp;</span>idx_visitor<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">               Ts<span style="color:#808030; ">&amp;</span><span style="color:#808030; ">&amp;</span> <span style="color:#808030; ">.</span><span style="color:#808030; ">.</span><span style="color:#808030; ">.</span> args<span style="color:#808030; ">)</span> <span style="color:#800000; font-weight:bold; ">const</span><span style="color:#800080; ">;</span></span>
<span class="line_wrapper"></span></pre>
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      <td>
        Same as groupby2() above, but executed asynchronously
      </td>
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<pre class="code_syntax" style="color:#000000;background:#ffffff00;"><span class="line_wrapper"><span style="color:#800000; font-weight:bold; ">template</span><span style="color:#800080; ">&lt;</span><span style="color:#800000; font-weight:bold; ">typename</span> T1<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> T2<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> T3<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">         <span style="color:#800000; font-weight:bold; ">typename</span> I_V<span style="color:#808030; ">,</span> <span style="color:#800000; font-weight:bold; ">typename</span> <span style="color:#808030; ">.</span><span style="color:#808030; ">.</span><span style="color:#808030; ">.</span> Ts<span style="color:#800080; ">&gt;</span></span>
<span class="line_wrapper"><span style="color:#666616; ">std</span><span style="color:#800080; ">::</span>future<span style="color:#800080; ">&lt;</span>DataFrame<span style="color:#800080; ">&gt;</span></span>
<span class="line_wrapper">groupby3_async<span style="color:#808030; ">(</span><span style="color:#800000; font-weight:bold; ">const</span> <span style="color:#800000; font-weight:bold; ">char</span> <span style="color:#808030; ">*</span>col_name1<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">               <span style="color:#800000; font-weight:bold; ">const</span> <span style="color:#800000; font-weight:bold; ">char</span> <span style="color:#808030; ">*</span>col_name2<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">               <span style="color:#800000; font-weight:bold; ">const</span> <span style="color:#800000; font-weight:bold; ">char</span> <span style="color:#808030; ">*</span>col_name3<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">               I_V <span style="color:#808030; ">&amp;</span><span style="color:#808030; ">&amp;</span>idx_visitor<span style="color:#808030; ">,</span></span>
<span class="line_wrapper">               Ts<span style="color:#808030; ">&amp;</span><span style="color:#808030; ">&amp;</span> <span style="color:#808030; ">.</span><span style="color:#808030; ">.</span><span style="color:#808030; ">.</span> args<span style="color:#808030; ">)</span> <span style="color:#800000; font-weight:bold; ">const</span><span style="color:#800080; ">;</span></span>
<span class="line_wrapper"></span></pre>
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      <td>
        Same as groupby3() above, but executed asynchronously
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<pre style='color:#000000;background:#ffffff00;'><span style='color:#800000; font-weight:bold; '>static</span> <span style='color:#800000; font-weight:bold; '>void</span> test_groupby<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span>  <span style='color:#800080; '>{</span>

    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>cout</span> <span style='color:#808030; '>&lt;</span><span style='color:#808030; '>&lt;</span> <span style='color:#800000; '>"</span><span style='color:#0f69ff; '>\n</span><span style='color:#0000e6; '>Testing groupby( ) ...</span><span style='color:#800000; '>"</span> <span style='color:#808030; '>&lt;</span><span style='color:#808030; '>&lt;</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>endl</span><span style='color:#800080; '>;</span>

    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#800080; '>></span>  ulgvec2 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123451</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123452</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123455</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123449</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123451</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123452</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123455</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span>
          <span style='color:#008c00; '>123454</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123457</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123458</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123459</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123441</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123442</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123432</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123435</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#800080; '>></span>  xulgvec2 <span style='color:#808030; '>=</span> ulgvec2<span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span>            intvec2 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#008c00; '>1</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>4</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>5</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>7</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>9</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>10</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>14</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>36</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>45</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span>         xdblvec2 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#008c00; '>10</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>20</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>11</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>11</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>30</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>40</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>50</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>40</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>60</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>70</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>80</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>90</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>50</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>100</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>11</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>25</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>20</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>30</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>1</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>4</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>12</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>6</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>10</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>4</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>5</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span>         dblvec22 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#008000; '>0.998</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.056</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.15678</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.923</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.06743</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.1</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.07865</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>0.9999</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.1002</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>0.8888</span><span style='color:#808030; '>,</span>
          <span style='color:#008000; '>0.14</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.0456</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>0.8999</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.01119</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.8002</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.2</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.1056</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.87865</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>0.6999</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.1902</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>1.545</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span>    strvec2 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>A</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>B</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>C</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>D</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>X</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>Y</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>W</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>P</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>Z</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>S</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>M</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>B</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
          <span style='color:#800000; '>"</span><span style='color:#0000e6; '>A</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>H</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>X</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>Q</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>V</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>P</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>W</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>K</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>I</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>L</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>J</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>N</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>Y</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>G</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>T</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>U</span><span style='color:#800000; '>"</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>

    MyDataFrame df<span style='color:#800080; '>;</span>

    df<span style='color:#808030; '>.</span>load_data<span style='color:#808030; '>(</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>move</span><span style='color:#808030; '>(</span>ulgvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> intvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> xdblvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> dblvec22<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> strvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>ul_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> xulgvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    <span style='color:#800000; font-weight:bold; '>auto</span>    fut1 <span style='color:#808030; '>=</span> df<span style='color:#808030; '>.</span>groupby1_async<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span>DF_INDEX_COL_NAME<span style='color:#808030; '>,</span>
                                                    LastVisitor<span style='color:#800080; '>&lt;</span>MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#808030; '>,</span> MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span> 
                                                    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_str</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>max_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MaxVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>min_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MinVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
    <span style='color:#800000; font-weight:bold; '>auto</span>    result1 <span style='color:#808030; '>=</span> fut1<span style='color:#808030; '>.</span>get<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    result1<span style='color:#808030; '>.</span>write<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>ostream</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>double</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>cout</span><span style='color:#808030; '>,</span> io_format<span style='color:#800080; '>::</span>csv2<span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    <span style='color:#800000; font-weight:bold; '>auto</span>    fut2 <span style='color:#808030; '>=</span> df<span style='color:#808030; '>.</span>groupby1_async<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>ul_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
                                                    LastVisitor<span style='color:#800080; '>&lt;</span>MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#808030; '>,</span> MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span> 
                                                    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_str</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>max_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MaxVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>min_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MinVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
    <span style='color:#800000; font-weight:bold; '>auto</span>    result2 <span style='color:#808030; '>=</span> fut2<span style='color:#808030; '>.</span>get<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    result2<span style='color:#808030; '>.</span>write<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>ostream</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>double</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>int</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>cout</span><span style='color:#808030; '>,</span> io_format<span style='color:#800080; '>::</span>csv2<span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    <span style='color:#800000; font-weight:bold; '>auto</span>    fut3 <span style='color:#808030; '>=</span> df<span style='color:#808030; '>.</span>groupby1_async<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
                                             MaxVisitor<span style='color:#800080; '>&lt;</span>MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#808030; '>,</span> MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span> 
                                             <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_str</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                             <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>max_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MaxVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                             <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>min_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MinVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                             <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
    <span style='color:#800000; font-weight:bold; '>auto</span>    result3 <span style='color:#808030; '>=</span> fut3<span style='color:#808030; '>.</span>get<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    result3<span style='color:#808030; '>.</span>write<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>ostream</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>double</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>cout</span><span style='color:#808030; '>,</span> io_format<span style='color:#800080; '>::</span>csv2<span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
<span style='color:#800080; '>}</span>

<span style='color:#696969; '>// -----------------------------------------------------------------------------</span>

<span style='color:#800000; font-weight:bold; '>static</span> <span style='color:#800000; font-weight:bold; '>void</span> test_groupby_2<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span>  <span style='color:#800080; '>{</span>

    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>cout</span> <span style='color:#808030; '>&lt;</span><span style='color:#808030; '>&lt;</span> <span style='color:#800000; '>"</span><span style='color:#0f69ff; '>\n</span><span style='color:#0000e6; '>Testing groupby_2( ) ...</span><span style='color:#800000; '>"</span> <span style='color:#808030; '>&lt;</span><span style='color:#808030; '>&lt;</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>endl</span><span style='color:#800080; '>;</span>

    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#800080; '>></span>  ulgvec2 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123451</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123452</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123455</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123449</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123451</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123452</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123455</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span>
          <span style='color:#008c00; '>123454</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123457</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123458</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123459</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123441</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123442</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123432</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123435</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>123450</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#800080; '>></span>  xulgvec2 <span style='color:#808030; '>=</span> ulgvec2<span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span>            intvec2 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#008c00; '>1</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>4</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>5</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>7</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>9</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>10</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>14</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>36</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>45</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span>         xdblvec2 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#008c00; '>10</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>20</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>11</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>11</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>30</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>40</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>50</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>40</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>60</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>70</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>80</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>90</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>50</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>100</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>11</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>25</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>20</span><span style='color:#808030; '>,</span>
          <span style='color:#008c00; '>30</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>1</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>4</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>12</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>6</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>10</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>4</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>5</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span>         dblvec22 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#008000; '>0.998</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.056</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.15678</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.923</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.06743</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.1</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.07865</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>0.9999</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.1002</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>0.8888</span><span style='color:#808030; '>,</span>
          <span style='color:#008000; '>0.14</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.0456</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>0.8999</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.01119</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.8002</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.2</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.1056</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.87865</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>0.6999</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.1902</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>1.545</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span>    strvec2 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>A</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>B</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>C</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>D</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>X</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>Y</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>W</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>P</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>Z</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>S</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>M</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>B</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
          <span style='color:#800000; '>"</span><span style='color:#0000e6; '>A</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>H</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>X</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>Q</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>V</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>P</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>W</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>K</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>I</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>L</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>J</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>N</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>Y</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>G</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>T</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>U</span><span style='color:#800000; '>"</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>

    MyDataFrame df<span style='color:#800080; '>;</span>

    df<span style='color:#808030; '>.</span>load_data<span style='color:#808030; '>(</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>move</span><span style='color:#808030; '>(</span>ulgvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> intvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> xdblvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> dblvec22<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> strvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>ul_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> xulgvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    <span style='color:#800000; font-weight:bold; '>auto</span>    result1 <span style='color:#808030; '>=</span> df<span style='color:#808030; '>.</span>groupby2<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span>DF_INDEX_COL_NAME<span style='color:#808030; '>,</span>
                                                         <span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
                                                         LastVisitor<span style='color:#800080; '>&lt;</span>MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#808030; '>,</span> MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span> 
                                                         <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_str</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                         <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>max_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MaxVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                         <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>min_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MinVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                         <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>cnt_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> CountVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                         <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    result1<span style='color:#808030; '>.</span>write<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>ostream</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>double</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>size_t</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>cout</span><span style='color:#808030; '>,</span> io_format<span style='color:#800080; '>::</span>csv2<span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    <span style='color:#800000; font-weight:bold; '>auto</span>    result2 <span style='color:#808030; '>=</span> df<span style='color:#808030; '>.</span>groupby2<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
                                                         DF_INDEX_COL_NAME<span style='color:#808030; '>,</span>
                                                         MinVisitor<span style='color:#800080; '>&lt;</span>MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#808030; '>,</span> MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span> 
                                                         <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_str</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                         <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>max_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MaxVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                         <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>min_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MinVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                         <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>cnt_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> CountVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                         <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    result2<span style='color:#808030; '>.</span>write<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>ostream</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>double</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>size_t</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>cout</span><span style='color:#808030; '>,</span> io_format<span style='color:#800080; '>::</span>csv2<span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    <span style='color:#800000; font-weight:bold; '>auto</span>    result3 <span style='color:#808030; '>=</span> df<span style='color:#808030; '>.</span>groupby2<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
                                               <span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
                                               MaxVisitor<span style='color:#800080; '>&lt;</span>MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#808030; '>,</span> MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span> 
                                               <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_str</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                               <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>max_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MaxVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                               <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>min_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MinVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                               <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>cnt_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> CountVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                               <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    result3<span style='color:#808030; '>.</span>write<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>ostream</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>double</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>size_t</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>cout</span><span style='color:#808030; '>,</span> io_format<span style='color:#800080; '>::</span>csv2<span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    <span style='color:#800000; font-weight:bold; '>auto</span>    result4 <span style='color:#808030; '>=</span> df<span style='color:#808030; '>.</span>groupby2<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
                                               <span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
                                               FirstVisitor<span style='color:#800080; '>&lt;</span>MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#808030; '>,</span> MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span> 
                                               <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_str</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                               <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>max_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MaxVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                               <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>min_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MinVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                               <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>cnt_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> CountVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                               <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    result4<span style='color:#808030; '>.</span>write<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>ostream</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>double</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>size_t</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>cout</span><span style='color:#808030; '>,</span> io_format<span style='color:#800080; '>::</span>csv2<span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    <span style='color:#800000; font-weight:bold; '>auto</span>    result5 <span style='color:#808030; '>=</span> df<span style='color:#808030; '>.</span>groupby2<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
                                                              DF_INDEX_COL_NAME<span style='color:#808030; '>,</span>
                                                              FirstVisitor<span style='color:#800080; '>&lt;</span>MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#808030; '>,</span> MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span> 
                                                              <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_str</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                              <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>max_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MaxVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                              <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>min_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MinVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                              <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>cnt_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> CountVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                              <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    result5<span style='color:#808030; '>.</span>write<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>ostream</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>double</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>size_t</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>cout</span><span style='color:#808030; '>,</span> io_format<span style='color:#800080; '>::</span>csv2<span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
<span style='color:#800080; '>}</span>
</pre>
<!--Created using ToHtml.com on 2021-04-07 17:23:00 UTC -->

<pre style='color:#000000;background:#ffffff00;'>
<span style='color:#696969; '>// -----------------------------------------------------------------------------</span>

<span style='color:#800000; font-weight:bold; '>static</span> <span style='color:#800000; font-weight:bold; '>void</span> test_groupby_3<span style='color:#808030; '>(</span><span style='color:#808030; '>)</span>  <span style='color:#800080; '>{</span>

    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>cout</span> <span style='color:#808030; '>&lt;</span><span style='color:#808030; '>&lt;</span> <span style='color:#800000; '>"</span><span style='color:#0f69ff; '>\n</span><span style='color:#0000e6; '>Testing groupby_3( ) ...</span><span style='color:#800000; '>"</span> <span style='color:#808030; '>&lt;</span><span style='color:#808030; '>&lt;</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>endl</span><span style='color:#800080; '>;</span>

    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#800080; '>></span>  ulgvec2 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#008c00; '>1</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>4</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>5</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>5</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>6</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>6</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>6</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>7</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>8</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>9</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>10</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>10</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>10</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>11</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>11</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>11</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>12</span><span style='color:#808030; '>,</span>
          <span style='color:#008c00; '>13</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>13</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>14</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>15</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>16</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>17</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>17</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#800080; '>></span>  xulgvec2 <span style='color:#808030; '>=</span> ulgvec2<span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span>            intvec2 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#008c00; '>1</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>4</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>5</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>7</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>9</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>10</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>14</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>36</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>45</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span>         xdblvec2 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#008c00; '>10</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>20</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>20</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>11</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>30</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>40</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>50</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>50</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>50</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>50</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>80</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>90</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>50</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>11</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>11</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>25</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>20</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>30</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>1</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>6</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>2</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>3</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>10</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>4</span><span style='color:#808030; '>,</span> <span style='color:#008c00; '>5</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span>         dblvec22 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#008000; '>0.998</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.056</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.15678</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.923</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.06743</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.1</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.07865</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>0.9999</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.1002</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>0.8888</span><span style='color:#808030; '>,</span>
          <span style='color:#008000; '>0.14</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.0456</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>0.8999</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.01119</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.8002</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.2</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.1056</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.87865</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>0.6999</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>1.545</span><span style='color:#808030; '>,</span> <span style='color:#008000; '>0.1902</span><span style='color:#808030; '>,</span> <span style='color:#808030; '>-</span><span style='color:#008000; '>1.545</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>
    <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>vector</span><span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span>    strvec2 <span style='color:#808030; '>=</span>
        <span style='color:#800080; '>{</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>A</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>A</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>A</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>B</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>C</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>C</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>C</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>C</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>Z</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>S</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>M</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>B</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
          <span style='color:#800000; '>"</span><span style='color:#0000e6; '>A</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>H</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>X</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>B</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>Y</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>Y</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>W</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>K</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>K</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>K</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>J</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>N</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>Y</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>G</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>K</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>B</span><span style='color:#800000; '>"</span> <span style='color:#800080; '>}</span><span style='color:#800080; '>;</span>

    MyDataFrame df<span style='color:#800080; '>;</span>

    df<span style='color:#808030; '>.</span>load_data<span style='color:#808030; '>(</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>move</span><span style='color:#808030; '>(</span>ulgvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> intvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> xdblvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> dblvec22<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> strvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                 <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_pair<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>ul_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> xulgvec2<span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    <span style='color:#800000; font-weight:bold; '>auto</span>    result1 <span style='color:#808030; '>=</span>
        df<span style='color:#808030; '>.</span>groupby3<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>unsigned</span> <span style='color:#800000; font-weight:bold; '>long</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
                                                        DF_INDEX_COL_NAME<span style='color:#808030; '>,</span>
                                                        <span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span>
                                                        LastVisitor<span style='color:#800080; '>&lt;</span>MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#808030; '>,</span> MyDataFrame<span style='color:#800080; '>::</span>IndexType<span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                        <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>str_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_str</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                        <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>max_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MaxVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                        <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>xint_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>min_int</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> MinVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                        <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col_2</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>cnt_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> CountVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>,</span>
                                                        <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span>make_tuple<span style='color:#808030; '>(</span><span style='color:#800000; '>"</span><span style='color:#0000e6; '>dbl_col</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> <span style='color:#800000; '>"</span><span style='color:#0000e6; '>sum_dbl</span><span style='color:#800000; '>"</span><span style='color:#808030; '>,</span> SumVisitor<span style='color:#800080; '>&lt;</span><span style='color:#800000; font-weight:bold; '>double</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>

    result1<span style='color:#808030; '>.</span>write<span style='color:#800080; '>&lt;</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>ostream</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>string</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>double</span><span style='color:#808030; '>,</span> <span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>size_t</span><span style='color:#808030; '>,</span> <span style='color:#800000; font-weight:bold; '>int</span><span style='color:#800080; '>></span><span style='color:#808030; '>(</span><span style='color:#666616; '>std</span><span style='color:#800080; '>::</span><span style='color:#603000; '>cout</span><span style='color:#808030; '>,</span> io_format<span style='color:#800080; '>::</span>csv2<span style='color:#808030; '>)</span><span style='color:#800080; '>;</span>
<span style='color:#800080; '>}</span>
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